In this study, we examine how the within-person variability of situational factors influences apprentices' informal learning, using the CAM-OS model as a conceptual framework. The CAM-OS model posits that the situational readiness factors of opportunity and support play a crucial role in shaping informal learning processes. Our mixed-methods approach combines a quantitative diary study and qualitative interviews to provide a comprehensive understanding of these dynamics. Participants included 127 apprentices and dual students from a medium-sized manufacturing company in Germany, who provided data over 837 daily records, supplemented by interviews with trainers and apprentices. Our findings confirm that learning opportunities, job control, and role clarity positively relate to self-based informal learning. Learning opportunities also positively relate to social-based informal learning, while job control and role clarity do not. Peer and supervisor support were not significantly related to self-based informal learning, but peer support was strongly associated with social-based informal learning. The interviews further highlighted apprentices' preferences for clear objectives combined with autonomy, as well as their strong reliance on peer interactions for knowledge exchange and reassurance. Notably, while trainers initiate learning through task assignments, their direct involvement in subsequent informal learning processes appears to be limited.
The study extends the CAM-OS model by differentiating between self-based and social-based informal learning, revealing that structural work characteristics primarily support self-based learning, whereas relational characteristics like peer support foster social-based learning. These insights suggest that apprentices' informal learning is highly dependent on a balance between autonomy and guidance. The qualitative findings also highlight the importance of accessible learning resources, role clarity, and defined goals, which help apprentices structure their learning experiences effectively. To support apprentices' informal learning, organizations should focus on designing a work environment rich in learning opportunities, clearly defining roles and expectations, and leveraging peer support through collaborative tasks and mentoring programs.